Gas turbine combustors are the subject of continual improvement, to provide better cooling, better mixing, better fuel efficiency, better performance, etc. at a lower cost. For example, heat shields are known to provide better protection to the combustor, but heat shields also require cooling.
The cold side of the heat shield can be cooled by impingement cooling provided through holes in the combustor shell. The cooling of the hot side of the heat shield is more challenging in that the cooling air has to be brought to the hot side of the heat shield, i.e. the side that faces away from the combustor shell. In previous heat shield designs, the cooling air for the hot side was provided by relatively expensive multi-part floating collars, or by complex machined devices.